| 摘要 |
The apparatus includes two tanks (4,5) each containing a stack (14,15) of metallic grids for periodic storage of heat extracted from the stale air, which is inducted through a dust filter (2) and fan (1) into each tank in turn via cyclically programmed (13) electrically operated valves (3). Fresh air is drawn through another filter (11) and fan (10) and similar valves (12) into whichever tank is not being supplied with the stale air. The two half-cycles are programmed to be of exactly equal duration. |
